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  Saving and Opening Cisco PathTracer Map Files
Saving and Opening Cisco PathTracer Map Files
Prime Network enables you to export multiple-path trace maps that are displayed in the Cisco PathTracer 
window to an XML file. You can view the data later to assess whether anything has changed.
Saving Cisco PathTracer Map Files
To save Cisco PathTracer map files:
Step 1Open the Cisco PathTracer window as described in Launching Path Tracer, page 13-2.
Step 2Click Save MultiPath in the toolbar.
Step 3In the Save dialog box, navigate to the directory where you want to save the file and enter a name for the 
map file.
Step 4Click Save. The map file is saved in the selected directory.
Opening Cisco PathTracer Map Files
Prime Network enables you to open saved XML-formatted path-tracing maps.
The following conditions apply when working with multiple-path trace files: 
When you load a multiple-path trace file, Prime Network queries the file (not the network), and 
loads the persisted information. 
If you load a multiple-path trace file that does not contain the same start and end points, the map is 
automatically opened in a new Cisco PathTracer window.
To open Cisco PathTracer map files:
Step 1In the Vision client, choose File > Load MultiPath from the main menu. The Open dialog box is 
displayed.
Step 2Navigate to the directory of the saved file and select the file.
Step 3Click Open. The previously saved map is displayed in the Cisco PathTracer window.
Saving Cisco PathTracer Counter Values
Prime Network enables you to export, over a period of time, the counter values of the path displayed in 
the Cisco PathTracer window to a CSV file. The data can then be viewed later, as required.
NoteThis topic applies to the Cisco PathTracer details window only.
To save Cisco PathTracer counter values that are generated over a period of time: 
Step 1Open the Cisco PathTracer details window as described in Launching Path Tracer, page 13-2. 
Step 2Click Start Saving to File in the toolbar. 
						

							  
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  Rerunning a Path and Comparing Results
Step 3In the Export Table to File dialog box, navigate to the directory where you want to save the 
Cisco PathTracer counter values. 
Step 4In the File name field, enter a name for the file in which to save the counter values.
Step 5Click Save. Cisco PathTracer starts saving the counter values to the specified file.
Step 6To stop exporting counter values to the file, click Stop Saving to File in the toolbar.
Cisco PathTracer stops exporting the counter values to the file.
Rerunning a Path and Comparing Results
If you save a path to a file (see Saving and Opening Cisco PathTracer Map Files, page 13-17), you can 
use the file to rerun the same path automatically with the same source and destination. You can also 
compare the saved path to a newly run path to determine if the path has changed or to assess a problem. 
To rerun a saved path: 
Step 1Load the required map file as described in Saving and Opening Cisco PathTracer Map Files, page 13-17. 
The Cisco PathTracer window is displayed with the previously saved map file.
Step 2Click Run Again in the toolbar.
The path trace runs automatically using the same source and destination as the loaded map file, and a 
new tab is displayed in the Cisco PathTracer window with the updated map. The tab displays the date 
and time when the path was rerun.
Step 3Compare the previous map to the updated one by switching between the tabs in the Cisco PathTracer 
window.
Note If you load a Cisco PathTracer map file that does not contain the same source and destination 
information as the map that is currently displayed in the window, the map is automatically opened 
in a new Cisco PathTracer window.
If you load a Cisco PathTracer map file that contains the same source and destination information 
as a map that is currently displayed in the window, the map is loaded in a new tab in the same 
window.
Viewing Q-in-Q Path Information 
The Q-in-Q (IEEE 802.1) tagging technology (also known as Dot1q tunneling) allows the nesting of 
another VLAN tag in a packet, in addition to an existing one. Either VLAN tag is considered an 802.1Q 
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  Viewing L2TP Path Information
Cisco PathTracer uses the VLAN tags of the Ethernet header and the port configuration to trace the path 
from one interface to another over the network. Among other things, you can:
View a Layer 2 path across a LAN domain with all the VLAN tag information.
For each network element, view the relevant parameters for each interface on all layers along the 
path.
Q-in-Q and Dot1q information is displayed in the Cisco PathTracer window when a path is traced over 
Ethernet ports with Dot1q and a Q-in-Q configuration.
As described in Launching Path Tracer, page 13-2, to view a specific path, you must specify an initial 
start point, such as an IP interface, and then an endpoint, such as a destination IP address. 
To trace a Q-in-Q path, you start the path from any:
Router or switch that is part of the Ethernet domain with Dot1q and Q-in-Q configurations.
IP destination that can be reached from that point of the network.
After you select the endpoint, the Cisco PathTracer window is displayed. From this window, you can 
open the Cisco PathTracer details window, with the appropriate Q-in-Q information displayed in the 
Layer 2 tab. 
The Layer 2 tab can display the following information specific to Q-in-Q and VLAN port configurations:
VLAN Mode—The work mode for the interface: Unknown, Access, Trunk, or Dot1Q Tunnel. Trunk 
mode also refers to multiple tagging.
Native VLAN ID—The VLAN identifier that is used to tag untagged traffic received on a trunked 
interface: 
–If VLAN tagging is enabled, the default native VLAN identifier is 1.
–If VLAN tagging is disabled, the native VLAN identifier is 0 (zero) or “no VLAN ID.” 
CE VLAN ID—The customer edge device VLAN identifier.
SP VLAN ID—The service provider VLAN identifier.
Viewing L2TP Path Information
Cisco PathTracer uses VC ID encapsulation information to trace the path from one tunnel interface to 
another over the network. The Cisco PathTracer tool enables you to:
View a path for the defined Layer 2 Tunneling Protocol (L2TP) session across the network.
For each network element, view the relevant parameters for each interface on all layers along the 
path.
The Layer 3 tab displays the peer name for L2TP tunnels. 
Table 13-3 describes the information that is displayed in the Layer 2 tab for L2TP tunnels. 
Table 13-3 Layer 2 Tab Information for L2TP Tunnels
Field Description
Encapsulation TypeEncapsulation type, such as Point-to-Point Protocol over ATM (PPPoA).
Binding Information Name of the subscriber.
Binding Status Binding status: bound or unbound.
Tunnel Session Count Number of current sessions. 
						

							  
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  Using Cisco PathTracer in MPLS Networks
Using Cisco PathTracer in MPLS Networks
You can open and view Cisco PathTracer information between service endpoints, such as an IP interface 
that is attached to the VRF over an MPLS network. The LSP in the MPLS network is found according 
to the cross-connect table of each router.
NoteAn LSP can be traced and displayed by Cisco PathTracer as part of an end-to-end tracing of a service; 
for example, when viewing a path between one CE device and another. Cisco PathTracer traces the path 
that goes over circuits or VLANs in the access networks. It also traces the LSPs between the VRFs going 
through all intermediate devices such as CE devices, aggregation switches, PE routers, and core routers.
To view a specific path, you must specify an initial starting point, such as an IP interface; specifying a 
destination IP address is optional. If the traced path (for example, a VC or VLAN) ends in a router, 
Cisco PathTracer finds the next hop according to the destination IP address. If you select an endpoint, 
Cisco PathTracer extracts the relevant IP address from this point and uses it as the destination.
The following topics provide more information on using Cisco PathTracer in MPLS networks: 
Cisco PathTracer MPLS Start and Endpoints, page 13-21
Using Cisco PathTracer for CSC Configurations, page 13-22
Using Cisco PathTracer for Layer 3 VPNs, page 13-22
Using Cisco PathTracer for Layer 2 VPNs, page 13-23
Using Cisco PathTracer for MPLS TE Tunnels, page 13-24 Tunnel Remote ID Remote tunnel identifier.
Tunnel ID Local tunnel identifier.
Tunnel Name Name of the subscriber and the tunnel identifier.
Session ID Session identifier.
Traffic>L2TPSession
CountersNumber of ingress traffic packets passing through the L2TP tunnel.
Traffic < 
L2TPSessionCountersNumber of egress traffic packets passing through the L2TP tunnel.
Tunnel Ctl Errors Number of control errors.
Tunnel State Tunnel state: unknown, idle, connecting, established, or disconnecting.
Session Type Session type: unknown, LAC, or LNS.
Peer Name Peer name.
Tunnel Remote IP Remote IP address of the tunnel.
Last Error Code Value of the last error code that caused the tunnel disconnection.
Session State Session state: unknown, idle, connecting, established, or disconnecting.
Remote Session ID Remote session identifier.
Table 13-3 Layer 2 Tab Information for L2TP Tunnels (continued)
Field Description 
						

							  
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Cisco PathTracer MPLS Start and Endpoints
You can open Cisco PathTracer by right-clicking a starting point and entering the required destination 
IP address. Table 13-4 lists the Cisco PathTracer starting points.
If you choose the Start Here option, Ta b l e 1 3 - 5 lists the endpoints that can be selected as path 
destinations.
The Cisco PathTracer window is displayed. From this window you can open the Cisco PathTracer details 
window with the VPN information displayed in the Layer 2 and Layer 3 tabs. 
NoteIf multiple paths are selected in the paths pane, or if nothing is selected in the paths pane, all available 
paths are opened automatically, and each is displayed in a separate Cisco PathTracer window.
Table 13-4 Cisco PathTracer MPLS Starting Points
Element Location Start Options
IP interface
Inventory window
Affected entity (enabled only if the 
affected entity has an IP interface)
From Here to Destination
Start Here
MPLS-TP tunnel 
endpoint
Navigation or map pane
Inventory window
From Here to Destination
Start Here
Site Service view map
From Here to Destination
To Subnet Destination
Start Here
Business tag 
attached to the 
VPI/VCI or IP 
interface The path can be found using a business tag, 
which is attached to the VPI/VCI or IP 
interface by entering its key. It can then be 
opened from the Find Business Tag window.From Here to Destination
Layer 2 MPLS 
TunnelInventory window From Here to Destination
Table 13-5 Cisco PathTracer MPLS Endpoints
Element Location End Options
IP interface
Inventory window
Affected entity (enabled only if the 
affected entity has an IP interface)End Here
MPLS-TP tunnel 
endpointInventory window End Here
Site Service view map End Here 
						

							  
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Using Cisco PathTracer for CSC Configurations
Cisco PathTracer traces a CSC flow from the customer CE through the customer carrier VPN, across the 
customer backbone carrier VPN, back to the customer carrier VPN, and to the destination CE. 
To launch a path trace for a CSC configuration: 
Step 1In a map, double-click the required CE device.
Step 2In the Inventory window, choose Logical Inventory > Routing Entities > Routing Entity. 
Step 3In the IP Interfaces table, right-click the required interface and choose PathTracer > Start Here >IPvn 
where IPvn represents IPv4 or IPv6. 
Step 4Navigate to the destination CE device and double-click it.
Step 5In the Inventory window, choose Logical Inventory > Routing Entities > Routing Entity. 
Step 6In the IP Interfaces table, right-click the required interface and choose PathTracer > End Here. 
The path trace is displayed in the Cisco PathTracer window.
Step 7To view the detailed pane, click Cisco PathTracer in the toolbar. 
The Layer 2 tab displays a single outer label and two inner labels for each interface, reflecting the CSC 
configuration. (See Figure 13-11.) 
Figure 13-11 CSC Configuration Path Trace
Using Cisco PathTracer for Layer 3 VPNs
Cisco PathTracer uses VRF routing and label switching information to trace the path from one VRF 
interface to another. If you choose a launch point and destination from the right-click menu, you can 
open the Cisco PathTracer for Layer 3 VPNs. The Cisco PathTracer window shows the VPN topology 
map. From this window, you can open the Cisco PathTracer details window with the appropriate VPN 
information displayed in the Layer 2 and Layer 3 tabs.  
						

							  
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For Layer 3 path information, Prime Network uses VRF routing and label switching information to trace 
the path from one VRF interface to another. Layer 3 path trace information is displayed in the 
Cisco PathTracer window when the path goes over connections and ends in VRFs. 
If a VRF table includes more than one path toward a destination, Cisco PathTracer shows all paths.
To view Layer 3 path information, choose the Layer 3 tab and choose Show All from the View menu. 
The path information is displayed in the active tab.
The table displays the Layer 3 VPN information on the device that has a VRF. The following Layer 3 
properties displayed in the Layer 3 tab relate specifically to VPNs:
Name—The name of the site. For example, ATM4/0.100(10.0.0.1) is a combination of the interface 
name and IP address used to reach the site. Each site belongs to a particular VPN, so the address 
must be unique within the VPN.
IP Address—The IP address of the interface.
Mask—The mask of the specific network.
State—The state of the interface (up or down).
VRF Name—The name of the VRF.
Cisco PathTracer does not display or trace EXP bits for Layer 3 VPNs that use policy-based tunnel 
selection (PBTS). 
Using Cisco PathTracer for Layer 2 VPNs
Cisco PathTracer uses VC ID and label switching information to trace the path from one tunnel interface 
to another over the MPLS network.
Cisco PathTracer also covers end-to-end Layer 2 VPN service paths from one CE router to another. The 
path goes over circuits (such as a VC) or VLANs in access networks and over LSP between the Layer 2 
tunnel edge.
The Cisco PathTracer window shows the VPN topology map for the relevant devices and links. From 
this window, you can open the Cisco PathTracer details window with the appropriate VPN information 
displayed in the Layer 2 and Layer 3 tabs. 
For Layer 2 path information, Cisco PathTracer uses VC ID, AGI, SAII, TAII, and label switching 
information to trace the path from one tunnel interface to another. Layer 2 path trace information is 
displayed in the Cisco PathTracer window when the path goes over pseudowire tunnels.
To view Layer 2 path information, choose the Layer 2 tab and then View > Show All. The path 
information is displayed in the active tab.
Table 13-6 describes the Layer 2 properties that can be displayed in the Layer 2 tab specifically for 
VPNs.
Table 13-6 Cisco PathTracer Layer 2 Properties for VPNs
Field Description
Top Label Details of the outer MPLS label.
Label Stack Details of the inner MPLS label.
MAC Address MAC address.
Tunnel ID Tunnel identifier. The identifier and the router IP address of the two 
tunnel edges identify the pseudowire tunnel. 
						

							  
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Using Cisco PathTracer for MPLS TE Tunnels
Cisco PathTracer uses label switching information to trace the end-to-end path of a TE tunnel path from 
one PE router to another.
Using MPLS TE technology, Cisco PathTracer enables you to:
View a path or list of devices.
View the following information for each network element:
–The relevant parameters for each interface on all layers along the path.
–The path for the defined MPLS TE-LSP across the network.
The Cisco PathTracer window is displayed showing the MPLS TE tunnel topology map. From this 
window, you can open the Cisco PathTracer details window with the appropriate MPLS TE tunnel 
information displayed in the Layer 2 tab.
NoteCisco PathTracer does not display or trace EXP bits for Layer 3 VPNs that use PBTS. 
Layer 2 and Layer 3 path trace information is displayed in the Cisco PathTracer details window when a 
path is traced over MPLS TE tunnels. To view Layer 2 path information, choose the Layer 2 tab and then 
View > Show All. The path information is displayed in the active tab. Tunnel Type Tunnel type: 
0—Unknown
1—PWE3
2—TE
Tunnel Status Operational state of the tunnel: Up or Down.
Tunnel Local VC Label MPLS label that is used by the router to identify or access the tunnel. It 
is inserted in the MPLS label stack by the local router.
Tunnel Peer VC Label MPLS label that is used by the router to identify or access the tunnel. It 
is inserted in the MPLS label stack by the peer router.
Tunnel Local Router IP IP address of the tunnel edge, which is used as the MPLS router 
identifier.
Tunnel Peer Router IP IP address of the peer tunnel edge, which is used as the MPLS router 
identifier.
Distribution Protocol 
Ty p eProtocol used by MPLS to build the tunnel, such as LDP or TDP.
Peer OID Tunnel identifier and device name.
Table 13-6 Cisco PathTracer Layer 2 Properties for VPNs (continued)
Field Description 
						

							  
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Table 13-7 describes the Layer 2 properties that can be displayed in the Layer 2 tab specifically for 
MPLS TE tunnels. 
Table 13-7 Cisco PathTracer Layer 2 Properties for MPLS TE Tunnels
Field Description
MPLS  TE  Properties MPLS TE data set in an MPLS interface, primarily bandwidth allocation 
levels and signaling protocol.
Tunnel Oper Status Operational status of the tunnel: Up or Down. 
If this value is Up, the Tunnel Admin Status must also be Up. See Tunnel 
Admin Status properties for additional information. 
Tunnel Bandwidth Kbps Configured bandwidth (in Kb/s) for the tunnel. 
Tunnel Description Description of the tunnel.
Tunnel Name Interface name.
Tunnel Admin Status Administrative status of the tunnel (Up or Down) with the following 
caveats:
If the Tunnel Oper Status value is Up, the Tunnel Admin Status 
value must also be Up. 
If the Tunnel Admin Status value is Down, the Tunnel Oper Status 
value must also be Down.
Tunnel Lockdown Whether or not the tunnel can be rerouted:
Enabled—The tunnel cannot be rerouted.
Disabled—The tunnel can be rerouted.
Tunnel LSP ID LSP identifier. 
Tunnel Auto Route Whether or not destinations behind the tunnel are routed through the 
tunnel: Enabled or disabled.
Tunnel Hold Priority Tunnel priority after path setup. 
Tunnel Setup Priority Tunnel priority upon path setup.
Tunnel Path Option Tunnel path option:
Dynamic—The tunnel is routed along the ordinary routing 
decisions after taking into account the tunnel constraints such as 
attributes, priority, and bandwidth. 
Explicit—The route is explicitly mapped with the included and 
excluded links.
Tunnel Out Label TE tunnel MPLS label distinguishing the LSP selection in the adjacent 
device.
Tunnel Affinity Tunnel’s preferential bits for specific links.
Tunnel Destination Address IP address of the device in which the tunnel ends.
Tunnel Peak Rate Kbps Peak flow specification (in Kb/s) for this tunnel.
Tunnel Out Interface Interface through which the tunnel exits the device.
Tunnel Burst Kbps Burst flow specification (in Kb/s) for this tunnel. 
						

							  
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Tunnel Average Rate Kbps Tunnel average rate in Kb/s.
Tunnel Affinity Mask Tunnel affinity bits that should be compared to the link attribute bits.
Table 13-7 Cisco PathTracer Layer 2 Properties for MPLS TE Tunnels (continued)
Field Description